Tensioning tools



Dec. 19, 1961 M. H. JONES 3,013,589

TENSIONING TOOLS Filed Dec. 21. 1959 5 Sheets-Sheet 1 Dec. 19, 1961 M.H. JONES 3,013,589

TENSIONING TOOLS Filed Dec. 21, 1959 5 Sheets-Sheet 2 Dec. 19, 1961 M.H. JONES 3,013,589

TENSIONING TOOLS Filed Dec. 21, 1959 5 Shgets-Sheet 5 U) 3,013,589TENSIONIN G TOOLS Maurice Holford Jones, Sutton Coldfield, England, as-

signor to Power Strapping Systems Limited, Birmingham, England, aBritish company Filed Dec. 21, 1959, Ser. No. 860,779 Claims priority,application Great Britain Dec. 23, 1958 14 Claims. (Cl. 148-12345) Thisinvention relates to tensioning tools used for tightening a loop ofbinding metal around a package prior to securing together overlappingends of the loop.

The present invention consists in a tensioning tool for tightening aloop of binding metal around a package, comprising tensioning meansincluding a rotary tensioner, for tightening the loop about the packageand an oscillatory driving lever, the drive being transmitted from thelever to the tensioner through a two-speed transmission.

The provision between the driving lever and the tensioner of atransmission having drives of different velocity ratio makes the toolparticularly suitable for operationby hand. The driving lever preferablyincorporates a manually operable speed selector mounted in a convenientposition so that it is readily accessible to the hand of the operativeworking the lever.

The rotary tensioner may be a capstan member around which one end of theloop of binding metal is wound. In operation the low velocity ratio isused to wind-in the surplus binding metal which on a large packet orcrate may be considerable and bring the loop closely into contact withits surface. As soon as appreciable resistance is felt a change is madeto the higher velocity ratio to obtain a greater mechanical advantage sothat final tension can be applied.

With a tool according to the present invention ordinary wire, flattenedwire or metal strip may be used as the binding metal.

An embodiment of the invention will now be described by way of examplewith reference to the accompanying drawings in which:

FIGURE 1 is a front elevation of a tensioning tool;

FIGURE 2 is a section on the line 2-2 in FIGURE 1;

FIGURE 3 is a part sectional front elevation of the driving lever orhandle;

FIGURE 4 is a section on the line 44 in FIGURE 3; FIGURE 5 is a rearperspective view of the drive transmitting mechanism of the tool;

FIGURE 6 is a front perspective view of the tool;

FIGURE 7 is a side elevationof the tool.

There is shown in the drawings a hand-operated tensioning tool themoving parts of which are mounted on or in a metal casing 10 whichcomprises a unitary member forming the front wall 11 and side walls 12and 13 of the casing, a back plate 14 and a roof 15. A downwardlycurving arm 16 projects from the top of the side wall 13 and, at itsouter extremity, meets the corner of a hat, L- shaped bar 17 projectinglaterally from'the bottom of the said side wall.

The tool is equipped with a gripper having a jaw 18 mounted by a pivot20 on an L-shaped bracket 21 that is rigidly connected to the front wallof the casing. The jaw is formed with a serrated face and is urged by aspring 22 into a position in which that face lies closely adjacent tothe serrated face of a pad or insert 19 of hardened metal which isfastened rigidly to the front of the casing beneath the bracket 21. Thespring 22 is housed in opposed pockets 23 which are formed in thebracket and the gripper and a handle 24 is provided on the gripper jawto enable it to be opened against the action of the spring.

The tool also possesses a guillotine comprising an anvil and a pivotedblade. The anvil 25 is formed with an States Patent upturned flange atits free end and is fixed to the front of the casing just above thelower edge thereof. The blade 26 is mounted by a pivot in a recess 27 inthe side wall 12 of the casing. The outer face of this recess is closedby a cover 28 and the forward end of the blade protrudes from aslot-like aperture in the front of the casing. Above the blade there ismounted a rotary spindle 29 carrying a handle 30, Between the walls ofthe recess 27 the spindle has a portion 31 of reduced diameter which isdisposed eccentrically with respect to the axis of rotation of thespindle and this eccentric portion is engaged and partially embraced bya curved edge of complementary shape on the blade 26 (see FIGURE 7). Theanvil carries a hard metal shear plate 25a with which the bladeco-operates when it is depressed by the eccentric portion of thespindle. The curved edge on the blade embracing the eccentric portionenables the blade to be lifted by the eccentric portion into itsinoperative position after performance of a cutting operation.

Inside the casing there are two parallel shafts, a driving shaft 32 anda driven shaft 33, which are journalled in bushed hearings in the frontwall 11 and the back-plate 14. The driven shaft 33 extends through thefront wall 11 and its forward end constitutes a rotary capstan 34 whichis situated outside the casing between the gripper and the guillotine.The capstan is quartered by two diametral slots which are adapted toreceive the free end of a loop of binding metal.

There are two gear trains connecting the driving shaft and the drivenshaft, a high speed gear train and a low speed gear train. The low speedgear train includes a small pinion 36 on the driving shaft and a largegear wheel 37 on the driven shaft, both pinion and gear wheel beingrigid with their shafts. The high speed gear train includes a gear wheel38 rotationally mounted on the driving shaft and a companion gear wheel39 of similar size which is rigid with the driven shaft. The drivinggear 38 has a long tubular boss 40 which surrounds the driving shaft,bearing bushes being provided between the shaft and the boss so that thegear 38 and its shaft can revolve independently of each other.

The tensioning tool includes an oscillatory driving lever or handle 41and which supplies the drive for the capstan 34 and there is a speedselector mechanism which can be operated to couple the handle to thecapstan through one or other of the gear trains.

The handle is loosely mounted on the tubular boss 40 of the driving gear38 and it protrudes to the exterior through a slot 42 in the roof of thecasing. The lower end of the handle is flanked by a pair of ratchetwheels one of which. the ratchet wheel 43, is mounted on the boss 49 andrigidly connected to the driving gear 38.

while the other, the ratchet wheel 44, is keyed to the driving shaftnext to the pinion 36. There is a pawl associated with each ratchetwheel and the two pawls are mounted by separate pivots one on each sideof the handle. wheel 44 and possesses a notched tail 46. The pawl 47 isengageable with the other ratchet wheel. There is a stop pawl 62 mountedin the lower part of the casing by a pivot 63, said pawl beingspring-urged into engage,- ment with the ratchet wheel 44. It will be.seen that owing to the presence of this stop pawl the rotary capstan ismovable in one direction only.

The handle is hollow and the lower end of its stepped bore contains atubular plunger 48 which is slidable in the bore. The plunger has asolid part carrying a pin 49 that extends on each side through slots 50in the wall of the handle. At one end the pin engages the notch in thetail of the pawl 45 and at the other it engages pawl 47 at a pointbetween the tooth and pivot of that pawl.

. The two pawls are thus turned in opposite directions The pawl 45 isengageable with the ratchet 3 when the plunger is reciprocated in thebore of the hamdle.

There is a speed selector member or push button 51 projecting from thetop of the handle and a push rod 52 extending between the push buttonand the tubular plunger. Midway between its ends the push button isformed with a collar 53 which is a sliding fit in the bore of the handleand the upper end of the button works in a guide bush 54 fitted into theopen end of the handle. The push rod is rigidly connected to the lowerend of the button. A helical spring 55 seats on a washer 56 in the boreof the handle, the upper end of the spring bearing against the undersideof the collar 53 so that the push button is normally protruded from thehandle.

The lower end of the push rod carries a pin 57 which passes through acap 58 closing the open end of the plunger and terminates in a head 59fitting slidably in the bore of the plunger between two compressionsprings 60, 61. These springs provide a resilient connection between thepush rod and the plunger.

It can be seen that in the normal position of the push button theplunger occupies its uppermost position in the bore of the handle andthe pawl 45 is held in resilient engagement with the associated ratchetwheel 44 by the upper spring 68 while the other pawl 47 is held clear ofratchet wheel 43. With the push button depressed the plunger occupiesits lowermost position and pawl 45 is now held clear of its ratchetwheel while the other pawl 47 is held resiliently in engagement withratchet wheel 43 by the lower spring 61.

In use the tensioning tool is placed on top of a package to be boundwith metal. One end of a length of metal strip trained by hand aroundthe package is fed from the right (as viewed in FIGURE 1) between thejaw 18 and pad 19 of the gripper and is passed below the anvil 25 so asto project beyond the tool on the left hand side. The other end of thestrip is passed over the anvil from tthe left and threaded into theslots of the capstan 34. A channel-shaped metal seal is then placedaround the overlapping portions of the strip to the left of the anvil.The tool is steadied by grasping the arm 16 and push button 51 isdepressed to engage pawl 47 with its ratchet wheel, thereby drivablyconnecting the handle to the capstan through the high speed gear train.The slack in the loop of metal is then rapidly taken up by oscillatingthe handle. During each driving stroke the handle, ratchet wheel 43 anddriving gear 38 turn freely in a counterclockwise direction on the shaft32 (as seen in FIGURE The motion of the gear 38 is transmitted to thedriven shaft and surplus metal is wound up on the capstan thus drawingthe loop into contact with the sides of the package. While the highspeed gear train is active the motion of the driven shaft 33 iscommunicated through gear 37 and pinion 36 to the driving shaft whichturns idly in its bearings. During each recovery stroke the handle movesby itself in a clockwise direction the pawl 47 overriding the teeth ofits ratchet. At the same time stop pawl 62 checks any tendency of thecapstan to recoil owing to accumulated tension in the loop of metal. Assoon as appreciable resistance to movement of the handle is felt thepush button is released to transfer the drive from the high speed to thelow speed gear train so that final tension can be applied to the loop ofbinding metal. The plunger 48 is urged to its uppermost position in thebore of the handle by the spring 55 thereby causing the pawls toexchange duties. The drive is transmitted to the capstan through pinion36 and gear wheel 37 and the driving gear 38 is now revolved idly on itsshaft by its companion gear 39.

As soon as final tension has been applied the channel shaped seal isclosed tightly upon the overlapping portion of the loop and notched orcrimped to fasten them securely together. The guillotine handle ispulled down to sever the free end of metal attached to the capstan fromthe loop. It will be noticed that the blade 26 cannot descend below theanvil to cut the loop itself because it is stopped by the floor of therecess in which it is housed (see FIGURE 7). The upturned flange at theend of the anvil prevents the free end of metal from being pushed offthe anvil during the cutting operation.

It will be apparent to those skilled in the art that the above describedembodiment of the invention is susceptible of many modifications. Forexample, the drive could be transmitted from the handle to the capstanby chain and sprocket instead of gears and some form of one-way clutchother than a ratchet could be used. Furthermore the capstan could takethe form of a friction wheel or roller mounted, as by an eccentricbearing, to press against the binding metal and move it longitudinallyon rotation of the wheel or roller, and the oscillatory driving lever orhandle could be arranged to drive the capstan or other rotary tensionerduring both of its oppositely directed strokes.

The essential features of the invention are pointed out in the appendedclaims and it is intended to cover all changes and modifications of theembodiment described by way of example which do not constitutedepartures from the spirit and scope of the invention.

I claim:

1. A tensioning tool, for tightening a loop of binding material around apackage, comprising tensioning means, including a rotary tensioner, fortightening the loop, an oscillatory driving lever, a two speedmechanical transmission between the driving lever and the tensionerincluding drives of difierent velocity ratio and speed selection meansselectively operable to couple the lever through said drives to thetensioner.

2. A tensioning tool, for tightening a loop of binding material around apackage, comprising tensioning means, including a rotary tensioner, fortightening the loop, an oscillatory handle for driving said tensioner,two speed drive transmission means between the handle and the tensionerand speed selection means, including a manually operable selector memberon the handle for selectively connecting said handle to said drive foroperating said tensioner at one or the other of its speeds.

3. A tensioning tool for tightening a loop of binding material around apackage, comprising tensioning means including a rotary tensioner, fortightening the loop, an oscillatory handle for driving said rotarytensioner, two speed drive transmission means including one way clutchmeans between the handle and the tensioner, and speed selection means,said clutch means being operable by the speed selection means to couplethe lever to the tensioner selectively through drives of ditferentvelocity ratio.

4. A tensioning tool for tightening a loop of binding material around apackage comprising a rotary tensioner for app ying tension to one end ofthe loop, a gripper for anchoring the other end of the loop, anoscillatory lever for driving said tensioner, separate drivetransmission means of different velocity ratio each including a one-wayclutch having input and output members, the output members of eachclutch being permanently coupled in driving relation to the tensionerand the corresponding input members being permanently coupled to thelever, means to prevent recoil of said rotary tensioner due to tensionin the loop and a selector member associated with the lever and operableto engage the input and output members of one or other of the clutches.

5. A tensioning tool, for tightening a loop of binding material around apackage, comprising a rotary tensioner for applying tension to one endof the loop, a g ipper for anchoring the loop near the other end, anoscillatory lever for driving said tensioner, two drive transmittingmechanisms of different velocity ratio each including a ratchet member,two pawls pivotally connected to the lever each pawl being associatedwith a different one of the ratchet members, means to prevent recoil ofsaid rotary tensioner due to tension in the loop, a selector membermounted on the lever and a linkage between the selector member and thepawls, so that the selector member is operable to engage one or other ofthe pawls with its associated ratchet member to place the lever indriving connection with the rotary tensioner.

6. A tensioning tool for tightening a loop of binding material around apackage, comprising a rotary tensioner for applying tension to one endof the loop, a gripper for anchoring the loop near the other end, anoscillatory lever for driving said tensioner, two drive transmittingmechanisms of different velocity ratio coupled to said tensioner andeach including a ratchet member, two pawls pivotally connected to thelever each pawl being associated with a different one of the ratchetmembers, a reciprocatory link joining the 'two pawls for simultaneouslymoving them in opposite senses between ratchet engaging and ratchetdisengaging positions, means to prevent recoil of said rotary tensionerdue to tension in the loop, a selector member on the lever, and aconnection between the selector member and said link, said selectormember being operable to shift the link so as to disengage the leverfrom one drive transmitting mechanism and engage it with the other.

7. A tensioning tool, for tightening a loop of binding material around apackage, comprising a rotary tensioner for applying tension to one endof the loop, a gripper for anchoring the loop near the other end, ahollow, driving lever mounted for oscillatory movement, two drivetransmitting mechanisms of different velocity ratio each including aratchet wheel, the drive for the tensioner being derived from said leveralternatively through the two mechanisms, means to prevent recoil ofsaid rotary tensioner due to tension in the loop, two pivoted pawlsmounted on opposite sides of the lever each pawl being associated with adifferent one of the ratchet members, a reciprocatory link joining thetwo pawls for simultaneously moving them in opposite senses betweenratchet engaging and ratchet disengaging positions, a slot in the leverhousing said link, a push rod movably mounted within the lever forshifting said link, a push button connected to the push rod andprojecting from the free end of the lever and a spring opposing inwardmovement of the push button.

8. A tensioning tool as claimed in claim 7 wherein the link is a pinextending transversely through the slot and projecting therefrom at eachend and further comprising a connection between the pin and one of thepawls at a point between the pivot and the tip of that pawl, a tail onthe other pawl, a connection between the tail and the pin, a tubularcoupling member slidably mounted within the lever and carrying the pin,a telescopic connection between the coupling member and the push rod anda spring housed within said telescopic connection.

9. A tensioning tool for tightening a loop of binding material around apackage, comprising tensioning means, including a rotary tensioner, fortightening the loop, an oscillatory lever for driving the tensioner, twogear trains of different velocity ratio, two ratchet clutches which arealternatively engageable to couple the lever drivably to the tensionerthrough either of the gear trains, means preventing movement of saidrotary tensioner in one direction and selector means for operablyconnecting said lever with one or other of said clutches.

10. A tensioning tool for tightening a loop of binding material around apackage, comprising a rotary tensioner for applying tension to one endof the loop, a gripper for anchoring the loop near the other end, anoscillatory driving handle, means to prevent movement of said rotarytensioner in one direction, two gear trains of dilferen-t velocityratio, two ratchet clutches which are alternatively engageable to couplethe handle drivably to the tensioner through a difierent one of the geartrains, and a selector member on the handle for operably connecting thelatter with one or other of said clutches.

11. A tensioning tool, for tightening a loop of binding material arounda package, comprising a rotary tensioner for applying tension to one endof the loop, a gripper for anchoring the loop near the other end, aguillotine adapted, after formation of a join in the loop, to sever fromthe join that end of the loop which is engaged by the tensioner, anoscillatory driving handle, two gear trains of different velocity ratio,two ratchet clutches which are alternatively engageable to couplethehandle drivably to the tensioner through a different one of the geartrains, means preventing movement of said tensioner in one direction anda selector member on the handle for operably connecting said handle withone or other of the clutches.

12. A tensioning tool, as claimed in claim 11 wherein the rotarytensioner compnises a slotted capstan, the slots in the capstan beingadapted to receive and frictionally to anchor one end of the loop, andthe guillotine comprises a fixed shear plate adapted to space apartoverlapping portions of the loop, a pivoted blade, an eccentric memberwhich is turnable to move said blade in-to co-operation with said shearplate and stop means for preventing movement of the blade beyond theshear plate.

13. A tensioning tool, for tightening a loop of binding material arounda package, comprising a driven shaft with two gear wheels, at capstan onsaid shaft, for applying tension to one end of the loop, a gripper foranchoring the other end of the loop, a driving shaft, a gear wheelloosely mounted on the driving shaft with a ratchet wheel drivablyconnected to it, a gear wheel rigid with the driving shaft with aratchet wheel drivably connected to it, the gear wheels of the twoshafts meshing to provide drives of different velocity ratio, a stoppawl associated with the last mentioned ratchet wheel, an oscillatoryhandle loosely mounted on the driving shaft between its gear wheels, twopawls pivotally connected to the handle, each pawl being associated witha different ratchet wheel, a push button on the handle and a linkageconnecting the push button to the pawls, so that the push button isoperable to engage one or other of the pawls with its ratchet wheel.

14. A tensioning tool, for tightening a loop of bind ing metal around apackage, comprising gripping means for anchoring one end of the loop,unidirectional rotary tensioning means for winding in the other end ofthe loop, an oscillatory driving handle, two-speed mechani caltransmission means drivably connecting said handle to said rotarytensioning means, and speed selection means associated with said handlefor selectively connecting the handle with said transmission means so asto operate said tensioning means at one speed or the other.

No references cited.

